Java String remove control characters from start and end

//package com.demo2s;

public class Main {
    public static void main(String[] argv) throws Exception {
        String str = "";
        System.out.println(clean(str));
    }//from  ww  w  . ja v a2  s  . c o m

    /**
     * The empty String <code>""</code>.
     * @since 2.0
     */
    public static final String EMPTY = "";

    /**
     * <p>Removes control characters (char &lt;= 32) from both
     * ends of this String, handling <code>null</code> by returning
     * an empty String ("").</p>
     *
     * <pre>
     * clean(null)          = ""
     * clean("")            = ""
     * clean("abc")         = "abc"
     * clean("    abc    ") = "abc"
     * clean("     ")       = ""
     * </pre>
     *
     * @see java.lang.String#trim()
     * @param str  the String to clean, may be null
     * @return the trimmed text, never <code>null</code>
     * @deprecated Use the clearer named {@link #trimToEmpty(String)}.
     *             Method will be removed in Commons Lang 3.0.
     */
    public static String clean(String str) {
        return str == null ? EMPTY : str.trim();
    }

    /**
     * <p>Removes control characters (char &lt;= 32) from both
     * ends of this String, handling <code>null</code> by returning
     * <code>null</code>.</p>
     *
     * <p>The String is trimmed using {@link String#trim()}.
     * Trim removes start and end characters &lt;= 32.
     * To strip whitespace use {@link #strip(String)}.</p>
     *
     * <p>To trim your choice of characters, use the
     * {@link #strip(String, String)} methods.</p>
     *
     * <pre>
     * trim(null)          = null
     * trim("")            = ""
     * trim("     ")       = ""
     * trim("abc")         = "abc"
     * trim("    abc    ") = "abc"
     * </pre>
     *
     * @param str  the String to be trimmed, may be null
     * @return the trimmed string, <code>null</code> if null String input
     */
    public static String trim(String str) {
        return str == null ? null : str.trim();
    }
}

/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */